904 resultados para Pure-component Diffusivities


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It is imperative to accept that failures can and will occur, even in meticulously designed distributed systems, and design proper measures to counter those failures. Passive replication minimises resource consumption by only activating redundant replicas in case of failures, as typically providing and applying state updates is less resource demanding than requesting execution. However, most existing solutions for passive fault tolerance are usually designed and configured at design time, explicitly and statically identifying the most critical components and their number of replicas, lacking the needed flexibility to handle the runtime dynamics of distributed component-based embedded systems. This paper proposes a cost-effective adaptive fault tolerance solution with a significant lower overhead compared to a strict active redundancy-based approach, achieving a high error coverage with the minimum amount of redundancy. The activation of passive replicas is coordinated through a feedback-based coordination model that reduces the complexity of the needed interactions among components until a new collective global service solution is determined, improving the overall maintainability and robustness of the system.

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Espresso coffee beverages prepared from pure origin roasted ground coffees from the major world growing regions (Brazil, Ethiopia, Colombia, India, Mexico, Honduras, Guatemala, Papua New Guinea, Kenya, Cuba, Timor, Mussulo and China) were characterized and compared in terms of their mineral content. Regular consumption of one cup of espresso contributes to a daily mineral intake varying from 0.002% (sodium; Central America) to 8.73% (potassium; Asia). The mineral profiles of the espresso beverages revealed significant inter- and intra-continental differences. South American pure origin coffees are on average richer in the analyzed elements except for calcium, while samples from Central America have generally lower mineral amounts (except for manganese). Manganese displayed significant differences (p < 0.05) among the countries of each characterized continent. Intercontinental and inter-country discrimination between the major world coffee producers were achieved by applying canonical discriminant analysis. Manganese and calcium were found to be the best chemical descriptors for origin.

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SUMMARY The molluscicidal activity of the leaf powder of Moringa oleifera and lyophilized fruit powder of Momordica charantia against the snail Lymnaea acuminata was time and concentration dependent. M. oleifera leaf powder (96 h LC50: 197.59 ppm) was more toxic than M. charantia lyophilized fruit powder (96 h LC50: 318.29 ppm). The ethanolic extracts of M. oleifera leaf powder and Momordica charantia lyophilized fruit powder were more toxic than other organic solvent extracts. The 96 h LC50 of the column purified fraction of M. oleifera leaf powder was 22.52 ppm, while that of M. charantia lyophilized fruit powder was 6.21 ppm. Column, thin layer and high performance liquid chromatography analysis show that the active molluscicidal components in M. oleifera leaf powder and lyophilized fruit of M. charantia are benzylamine (96 h LC50: 2.3 ppm) and momordicine (96 h LC50: 1.2 ppm), respectively. Benzylamine and momordicine significantly inhibited, in vivo and in vitro, the acetylcholinesterase (AChE), acid and alkaline phosphatase (ACP/ALP) activities in the nervous tissues of L. acuminata. Inhibition of AChE, ACP and ALP activity in the nervous tissues of L. acuminata by benzylamine and momordicine may be responsible for the molluscicidal activity of M. oleifera and M. charantia fruits, respectively.

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A dança e os espetáculos foram atividades desenvolvidas e praticadas pelo homem desde praticamente a sua existência. Ao longo de todo esse período de tempo e até aos dias atuais estas atividades foram sofrendo evoluções que as fizeram manterem-se relevantes e de grande importância na sociedade humana e na sua cultura. A evolução não se fez sentir apenas no estilo das danças e espetáculos mas também nos acessórios e efeitos que estas implementam de forma a torna-las mais atrativas para quem as vê. Apesar desta evolução, a maioria dos efeitos não permite um nível de interação com a dança ou espetáculo, fazendo com que exista uma clara separação entre a componente pura da dança e o cenário do espetáculo no que diz respeito á componente acessória de efeitos. Com o intuito de colmatar esta clara divisão de componentes, iniciamos um estudo no sentido de criar um sistema que permitisse derrubar essa barreira e juntar as duas componentes com o intuito de criar efeitos que interajam com a própria dança tornando o espetáculo mais interativo, e que não seja apenas mais um componente acessório, isto ao mesmo tempo torna todo o espetáculo mais apelativo para o público em geral. Para conseguir criar tal sistema, recorremos às tecnologias de sensores de movimento atuais para que a ponte de ligação entre o artista e os efeitos fosse conseguida. No mercado existem diversas ofertas de sensores de movimentos que serviriam para criar o sistema, mas apenas um poderia ser escolhido, então para tal numa primeira parte foi feito um estudo para determinar qual destes sensores seria o mais adequado para ser utilizado no sistema, tendo em conta uma diversidade de fatores. Após a escolha do sensor foi então desenvolvido o sistema MoveU e tendo no final sido feitos uma série de testes que permitiram validar o protótipo e verificar se os objetivos propostos foram atingidos. Por fim, o MoveU foi demonstrado a uma série de pessoas (dançarinos e espectadores), para que pudessem opinar sobre ele e indicar possíveis melhoramentos. Foram também criados uma série de questionários para que o público a quem foi demonstrado o protótipo, com a finalidade de realizar uma análise estatística para determinar se este sistema seria do agrado das pessoas e também permitir retirar conclusões sobre este trabalho.

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A Work Project, presented as part of the requirements for the Award of a Masters Degree in Finance from the NOVA – School of Business and Economics

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A competitive antibody enzyme immunoassay, using a monoclonal antibody against the species-specific Trypanosoma crnzi antigen 5, was used to investigate the presence of anti-component 5 antibodies in sera of opossums, dogs, rabbits and rats infected with this parasite. The sera from 51 Venezuelan patients with Chagas’disease were also tested. About 90% of the infected subjects showed significant levels of anti-component 5 antibodies. Nevertheless, these antibodies were not detected in the sera of dogs, rats and opossums infected with T. cruzl Some sera from infected rabbits presented significant results but close to the limit ofpositivity ofthe test. These findings suggest that the immune response in animals naturally or experimentally infected with T. cruzi is different from that observed in human Chagas’disease.

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Dissertação para obtenção do Grau de Mestre em Engenharia Química e Bioquímica

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Dissertação para obtenção do Grau de Mestre em Engenharia Informática

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Over the years, several formalizations and existence results for games with a continuum of players have been given. These include those of Schmeidler (1973), Rashid (1983), Mas-Colell (1984), Khan and Sun (1999) and Podczeck (2007a). The level of generality of each of these existence results is typically regarded as a criterion to evaluate how appropriate is the corresponding formalization of large games. In contrast, we argue that such evaluation is pointless. In fact, we show that, in a precise sense, all the above existence results are equivalent. Thus, all of them are equally strong and therefore cannot rank the different formalizations of large games.

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RESUMO: A violência contra as mulheres (VCM) é um problema de saúde pública e uma violação dos direitos humanos. Ele tem uma alta prevalência na América Latina e no Caribe; o Estudo da Violência Contra as Mulheres da Organização Mundial de Saúde (OMS) identificou que as mulheres peruanas sofrem o maior índice de violência. O Perú é signatário da CEDAW e da Convenção de Belém do Pará, com recomendações para resolver este tipo de discriminação e descrever o papel do setor da saúde. A lei peruana define a violência como um problema de saúde mental. Objectivos: As três orientações clínicas do Ministério da Saúde para avaliar a integração da componente de saúde mental no cuidado de mulheres afetadas pela VCM foram revistas. Método: A proteção da saúde mental foi avaliada nas orientações acima mencionadas. A lei peruana relevante para perceber o reconhecimento das consequências de VCM na saúde mental e os cuidados prestados neste contexto foram revistos. Usando esses padrões nacionais e internacionais, foi realizada uma análise de conteúdo dos guias peruanos para a atenção da violência para ver como eles se integram a saúde mental. Resultados: Estas orientações são muito extensas e não definem claramente a responsabilidade dos profissionais de saúde. Não incluem um exame de saúde mental na avaliação da vítima e são vagas na descrição das atividades a serem realizadas pelo prestador dos cuidados de saúde. As orientações recomendam uma triagem universal usando um instrumento com formato antiquado e pesado. Em contrapartida, as orientações da OMS não recomendam qualquer triagem. Conclusão: As várias orientações analisadas não fornecem a informação necessária para o profissional de saúde avaliar o envolvimento da saúde mental e, desnecessariamente, tratam as mulheres sobreviventes de VCM como doentes mentais. Recomenda-se que as orientações recentes da OMS (Responding to intimate partner violence and sexual violence against women: WHO clinical and policy guidelines, 2013) para os cuidados de VCM sejam usadas como um modelo para o desenvolvimento de um único dispositivo técnico que incorpora directrizes com base científica. legislação com base no género, saúde, guias, prevenção e mujeres 6 RESUMO (PORTUGUESE) A violência contra as mulheres (VCM) é um problema de saúde pública e uma violação dos direitos humanos. Ele tem uma alta prevalência na América Latina e no Caribe; o Estudo da Violência Contra as Mulheres da Organização Mundial de Saúde (OMS) identificou que as mulheres peruanas sofrem o maior índice de violência. O Perú é signatário da CEDAW e da Convenção de Belém do Pará, com recomendações para resolver este tipo de discriminação e descrever o papel do setor da saúde. A lei peruana define a violência como um problema de saúde mental. Objectivos: As três orientações clínicas do Ministério da Saúde para avaliar a integração da componente de saúde mental no cuidado de mulheres afetadas pela VCM foram revistas. Método: A proteção da saúde mental foi avaliada nas orientações acima mencionadas. A lei peruana relevante para perceber o reconhecimento das consequências de VCM na saúde mental e os cuidados prestados neste contexto foram revistos. Usando esses padrões nacionais e internacionais, foi realizada uma análise de conteúdo dos guias peruanos para a atenção da violência para ver como eles se integram a saúde mental. Resultados: Estas orientações são muito extensas e não definem claramente a responsabilidade dos profissionais de saúde. Não incluem um exame de saúde mental na avaliação da vítima e são vagas na descrição das atividades a serem realizadas pelo prestador dos cuidados de saúde. As orientações recomendam uma triagem universal usando um instrumento com formato antiquado e pesado. Em contrapartida, as orientações da OMS não recomendam qualquer triagem. Conclusão: As várias orientações analisadas não fornecem a informação necessária para o profissional de saúde avaliar o envolvimento da saúde mental e, desnecessariamente, tratam as mulheres sobreviventes de VCM como doentes mentais. Recomenda-se que as orientações recentes da OMS (Responding to intimate partner violence and sexual violence against women: WHO clinical and policy guidelines, 2013) para os cuidados de VCM sejam usadas como um modelo para o desenvolvimento de um único dispositivo técnico que incorpora directrizes com base científica.-----------------ABSTRACT: Violence against women (VAW) is a public health problem and a human rights violation. It is highly prevalent in Latin America and the Caribbean; the Multi-country Study on Violence against Women by the World Health Organization identified rural Peruvian women as suffering the highest rates of VAW. The country is party to CEDAW and Belen Do Para Conventions, which set forth recommendations to overcome this form of discrimination and describe the role of the health sector. Peruvian law defines violence as a mental health issue. Objective: The Ministry of Health’s three technical guidelines were reviewed to assess the integration of mental health into the care of women affected by violence Method: The protection of the woman’s mental health was ascertained in the conventions mentioned above. The recognition of the mental health consequences of VAW and the inclusion of its evaluation and care were assessed in pertinent Peruvian legislation. Using these international and national parameters, the three guidelines for the attention of violence were subject to content analysis to see whether they conform to the conventions and integrate mental health care. Outcome: These guidelines are too extensive and do not clearly define the responsibility of health workers. They do not include a mental health exam in the evaluation of the victim and are vague in the description of the actions to be carried out by the health care provider. Guidelines prescribe universal screening using an outdated instrument and moreover, WHO Guidelines do not recommend screening. Conclusion: These multiple guidelines do not provide useful guidance for health care providers, particularly for the assessment of mental health sequelae, and unnecessarily stigmatize survivors of violence as mentally ill. It is recommended that the World Health Organization’s document Responding to intimate partner violence and sexual violence against women: WHO clinical and policy guidelines (2013) be used as a blueprint for only one technical instrument that incorporates evidence -based national policy and guidelines.

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Nowadays, participatory processes attending the need for real democracy and transparency in governments and collectives are more needed than ever. Immediate participation through channels like social networks enable people to give their opinion and become pro-active citizens, seeking applications to interact with each other. The application described in this dissertation is a hybrid channel of communication of questions, petitions and participatory processes based on Public Participation Geographic Information System (PPGIS), Participation Geographic Information System (PGIS) and ‘soft’ (subjective data) Geographic Information System (SoftGIS) methodologies. To achieve a new approach to an application, its entire design is focused on the spatial component related with user interests. The spatial component is treated as main feature of the system to develop all others depending on it, enabling new features never seen before in social actions (questions, petitions and participatory processes). Results prove that it is possible to develop a working application mainly using open source software, with the possibility of spatial and subject filtering, visualizing and free download of actions within application. The resulting application empowers society by releasing soft data and defines a new breaking approach, unseen so far.

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This study focuses on the implementation of several pair trading strategies across three emerging markets, with the objective of comparing the results obtained from the different strategies and assessing if pair trading benefits from a more volatile environment. The results show that, indeed, there are higher potential profits arising from emerging markets. However, the higher excess return will be partially offset by higher transaction costs, which will be a determinant factor to the profitability of pair trading strategies. Also, a new clustering approach based on the Principal Component Analysis was tested as an alternative to the more standard clustering by Industry Groups. The new clustering approach delivers promising results, consistently reducing volatility to a greater extent than the Industry Group approach, with no significant harm to the excess returns.

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Application of Experimental Design techniques has proven to be essential in various research fields, due to its statistical capability of processing the effect of interactions among independent variables, known as factors, in a system’s response. Advantages of this methodology can be summarized in more resource and time efficient experimentations while providing more accurate results. This research emphasizes the quantification of 4 antioxidants extraction, at two different concentration, prepared according to an experimental procedure and measured by a Photodiode Array Detector. Experimental planning was made following a Central Composite Design, which is a type of DoE that allows to consider the quadratic component in Response Surfaces, a component that includes pure curvature studies on the model produced. This work was executed with the intention of analyzing responses, peak areas obtained from chromatograms plotted by the Detector’s system, and comprehending if the factors considered – acquired from an extensive literary review – produced the expected effect in response. Completion of this work will allow to take conclusions regarding what factors should be considered for the optimization studies of antioxidants extraction in a Oca (Oxalis tuberosa) matrix.

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The Electrohysterogram (EHG) is a new instrument for pregnancy monitoring. It measures the uterine muscle electrical signal, which is closely related with uterine contractions. The EHG is described as a viable alternative and a more precise instrument than the currently most widely used method for the description of uterine contractions: the external tocogram. The EHG has also been indicated as a promising tool in the assessment of preterm delivery risk. This work intends to contribute towards the EHG characterization through the inventory of its components which are: • Contractions; • Labor contractions; • Alvarez waves; • Fetal movements; • Long Duration Low Frequency Waves; The instruments used for cataloging were: Spectral Analysis, parametric and non-parametric, energy estimators, time-frequency methods and the tocogram annotated by expert physicians. The EHG and respective tocograms were obtained from the Icelandic 16-electrode Electrohysterogram Database. 288 components were classified. There is not a component database of this type available for consultation. The spectral analysis module and power estimation was added to Uterine Explorer, an EHG analysis software developed in FCT-UNL. The importance of this component database is related to the need to improve the understanding of the EHG which is a relatively complex signal, as well as contributing towards the detection of preterm birth. Preterm birth accounts for 10% of all births and is one of the most relevant obstetric conditions. Despite the technological and scientific advances in perinatal medicine, in developed countries, prematurity is the major cause of neonatal death. Although various risk factors such as previous preterm births, infection, uterine malformations, multiple gestation and short uterine cervix in second trimester, have been associated with this condition, its etiology remains unknown [1][2][3].

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The objective of the work presented in this thesis was the development of an innovative approach for the separation of enantiomers of secondary alcohols, combining the use of an ionic liquid (IL) - both as solvent for conducting enzymatic kinetic resolution and as acylating agent - with the use of carbon dioxide (CO2) as solvent for extraction. Menthol was selected for testing this reaction/separation approach due to the increasing demand for this substance, which is widely used in the pharmaceutical, cosmetics and food industries. With a view to using an ionic ester as acylating agent, whose conversion led to the release of ethanol, and due to the need to remove this alcohol so as to drive reaction equilibrium forward, a phase equilibrium study was conducted for the ehtanol/(±)-menthol/CO2 system, at pressures between 8 and 10 MPa and temperatures between 40 and 50 oC. It was found that CO2 is more selective towards ethanol, especially at the lowest pressure and highest temperature tested, leading to separation factors in the range 1.6-7.6. The pressure-temperature-composition data obtained were correlated with the Peng-Robinson equation of state and the Mathias-Klotz-Prausnitz mixing rule. The model fit the experimental results well, with an average absolute deviation (AAD) of 3.7 %. The resolution of racemic menthol was studied using two lipases, namely lipase from Candida rugosa (CRL) and immobilized lipase B from Candida antarctica (CALB), and two ionic acylating esters. No reaction was detected in either case. (R,S)-1-phenylethanol was used next, and it was found that with CRL low, nonselective, conversion of the alcohol took place, whereas CALB led to an enantiomeric excess (ee) of the substrate of 95%, at 30% conversion. Other acylating agents were tested for the resolution of (±)-menthol, namely vinyl esters and acid anhydrides, using several lipases and varying other parameters that affect conversion and enantioselectivity, such as substrate concentration, solvent and temperature. One such acylating agent was propionic anhydride. It was thus performed a phase equilibrium study on the propionic anhydride/CO2 system, at temperatures between 35 and 50 oC. This study revealed that, at 35 oC and pressures from 7 MPa, the system is monophasic for all compositions. The enzymatic catalysis studies carried out with propionic anhydride revealed that the extent of noncatalyzed reaction was high, with a negative effect on enantioselectivity. These studies showed also that it was possible to reduce considerably the impact of the noncatalyzed reaction relative to the reaction catalyzed by CRL by lowering temperature to 4 oC. Vinyl decanoate was shown to lead to the best results at conditions amenable to a process combining the use of supercritical CO2 as agent for post-reaction separation. The use of vinyl decanoate in a number of IL solvents, namely [bmim][PF6], [bmim][BF4], [hmim][PF6], [omim][PF6], and [bmim][Tf2N], led to an enantiomeric excess of product (eep) values of over 96%, at about 50% conversion, using CRL. In n-hexane and supercritical CO2, reaction progressed more slowly.(...)